Engine starter



M. P. WHITNEY 1,883,430

Oct, 1, 1932 v ENGINE STARTER Filed May 5, 1924 3 Sheets-Sheet l I. fax/m7 wazzimffmq fQZZnass @c%. 18, 1932. M. P. WHITNEY 1,383,430

ENGINE STARTER I Fil M y' 5, 1924 5 Sheets-Sheet 2 Oct. 18, 1932. M. P. WHITNEY 1,883,430

ENGINE STARTER File d May 5, 1924 3 srieets-sheet s WWW Patented Oct. 18, 1932 unireo STATES PATENT OFFICE MATTE/1GB P. WETNEY, F ELEDQA, NEW YORK, ASSIGNOR T0 EGLIPSE MACHDIE GQEL'EANY, 6F ELMIRA, NEW YORK, A OORPQR-ATION 0F'. HEW YORK nnenin smn'rnn Application filed Key 5,

My invention reletcs to en epperetns for starting en engine, more particularly an in ternal combustion engine, and pertains to the simple, efiicient end reliable drive cheracterized more particularly by the provision of two clutches arranged in the line of trans mission of torque and cooperating with both ends of e. yielding means, such as e. compression spring. My drive in its preferred form, in which entoinetic disconnection of the tronsmitting elements is possible, is edepted to take care of any load condition beyond 9. predetermined maximum (such as results from the backfire the engine or arrest of the longitudinal movement of the driving incinber or pinion from eny cause) which is liable to be injurious or destructive to the starting apparatus or to the engine member with which it is operetively connected.

While my invention is not limited in this application and use to any particular construction of apparatus or any particular form of drive, i have incorporated the same in well known Bendix drive and the some will, therefore. be described in connection therewith. Speaking in enerel terms, and referring to the preferre form, my new drive includes eroteteble member such as e. screw shaft end e driving member or pinion mounted thereon for longitudinal movement thereof and rotary movement therewith and adapted to be automatically edvenced into mesh with the engine member such as the flywheel. lhis screw shaft is driven by the extended armature shaft or s. conntersheft driven therefrom through c pair of yieldsble clutches working-upon the ends of a heavy coiled spring interposed between them. with the result that in case of overload the members of each clutch will disengage and break the driving connection be tween the armature shaft and the screw shaft and permit such'armcture shaft to run freely or idly. In this manner when the predetermined meximuln load is reached, the clutches Serial R0. 710,979.

are automatically declutched or disabled and the driving connection between the starting motor endthe screw shaft will thereupon be broken, and in' the case of backfire the pinion may be rotated by the flywheel in reverse direction without any injury to the part-s. In a modified form, the clutch members while also cooperating with both ends of the sprin are not permitted to disengage but to yiel one member of a clutch with respect tothe other, whereby there is provided an initial yielding drive and a. positive final drive.

In the drawings, Figure 1 is a sectional elevation of my starting apparatus; Fig. 2 an end view of the drive; Fig. 3 a detail view of the pinion stop; Figs. 4 and 5 cross sections on the same section line of Fig. 2 but looking in opposite directions as indicated by the arrows corresponding to the particular figure; Fig. 6 a. view' similar to Fig. 1 but showing more of the parts in elevation and less in section; Figs. 7 to 12 elevations of the clutch members; Fig.1? an end view of the screw shaft; Fig. 14- an elevation of the screw shaft; Fig. 15 an end view of the Jpinion; Fig. 16 a side elevation thereof; ig. 17 an end view of an actuating sleeve;

.Fig. 18 a. side elevation thereof; Fig. 19 an end elevation of the enclosing casing or barrel'; Fig. 20 a side elevation thereof; Fig. 21 one of the keys employed, and Fig. 22 e. detail of s. modified form of construction.

Referring to the particular embodiment of my invention as herein shown, the drive is here directly driven inasmuch as the driving sheft 1 is the extended armature sheft of the electric motor indicated at A, but it will be understood thst my invention is applicable to the indirect drive type in which the drive is mounted upon a. countersheft with respect to said armature shaft. Moreover, the particular drive shown is of the inboard type inasmuch as the driving member or pinion 2 moves inwardly when going into mesh with the flywheel, but it will be understood that my invention is equally applicable to a. drive of the outboard type.

Upon the driving shaft 1 there is mounted a rotatable member which in the present instance 1s m the form of e hollow screw shaft 3 on which the driving member or pinion is threaded. This pinion is thus mounted upon the screw shaft for rotary movement therewith and for longitudinal movement thereof to mesh with the teeth 4 of the flywheel 5 of the engine to be started. This longitudinal movement of the'pinion for the cranking operation is stopped by a stop nut 6 secured to the inner end of the screw shaft. In the present instance, there is no direct contact between the pinion andthe stop nut inasmuch as there is interposed between the pinion and the stop nut a collar 7 slidable longitudinally upon the smooth portion of the screw shaft and against the tension of a light spring 8. By preference, the pinionis provided at its outer or non-engaging end with a projecting disc 9 which may or may not be integral therewith, but which is here shown separate and secured thereto.

' The driving connection between the driving shaft 1 and the driven member 10 of the screw shaft comprises more particularly the yieldable clutches which constitute the feature of my present invention and consists of the following mechanism. A sleeve 11 is secured to thedriving shaft by means of the screw 12 and a key 13. This sleeve has the particular shape illustrated in Figs. 17 and pl 18 wherein it is seen that the same has two opposite flattened faces 14 and also a reduced outer diameter in order to form a. shoulder 15. It is upon this sleeve that the movable or longitudinally slidable members of both clutches and the fixed or non-sliding member of one of these clutches are mounted.

There are two clutches both of which are located within the casing or barrel 16 and arranged in the line of transmission of torque between the driving shaft 1 and the screw shaft. These clutches are positioned at opposite ends of this barrel and between them is interposed a heavy coiled compression spring 17. The outer clutch is composed of two members 18 and 19 which are illustrated separately in Figs. 7, 8, 9 and 10. These members have corresponding or complementary inclined clutch jaws 20 and 21 respectively so that the transmission of torque in excess of a predetermined amount will cause the clutch member 19, hereinafter for convenience called the movable member to slide longitudinally out of engagement with its corresponding member which is in-. capable of longitudinal movement and is, therefore, hereinafter for convenience called the fixed member although,- of course, it is capable of rotation. The fixed member 18 has a central circular bore fitting over the sleeve 11 and, therefore, not connected therewith. On the other hand, the other clutch member 19 has a central here which is of the same shape as the outer surface of the sleeve 11, that is it is provided with opposite fiat sides 22 as shown in Fig. 7 withthe result the slots24; and 25 of the barrel and clutch member 18 respectively. A ring 26 is secured threading thereon and the same is provided a with anfinwardly directed flange 27 fitting against the outer face of the clutch member 18 and against the shoulder 15 of the sleeve 11.

The inner clutch is substantially the same as the outer clutch with the exception that the fixed clutch member. 28 has an irregular shaped bore with flattened sides 29 whereby it is rotatably secured to the correspondingly flattened opposite sides 30 of the head 10 of the screw shaft. This fixed clutch member 28 is secured to the barrel 16 in the same manner as the clutch member 18, that is, by means of keys 23 interlocking with slots 31 and 32 of the barrel and clutch member 28 respectively. A ring 33 similar to the ring 27 is secured to the inner end of the barrel and has an inwardly directed flange 34 adapted to hold the clutch member 28 in ace. 7 The other clutch member 35 is similar to clutch member19 inasmuch as itis of the same structure and operation, that is, it has inclined jaws -36 engaging corresponding jaws 37 of its cooperating clutch member and is rotativelyconnected with and movable longitudinally upon the sleeve 11 against the tension of the spring 17. This spring is normally under a predetermined amount of tension which is exerted upon. the movable clutch members 19 and 35 in order to keep them separated from each other and into engagement with their cooperating clutch members 18 and 28.

As above stated, the clutch member 28 is rotatively secured to the head 10 of the screw shaft and in order to permit of the longitudinal movement of such shaft independently of this clutch member and against the tension of the coiled spring 38, and to also limit the outward movement of this screw shaft, I provide a dowel pin 39 which extends through an opening 40, that is coincident with the slot 32 of the clutch member 28 as shown in Figs. 1 andll. This pin screw shaft cooperates with the pin whereby the screw shaft is limited in its outward position' as enforced by said spring 38. When the parts are assembled, the pin 39 is held in place by the key 23 as shown in Fig. 1.

In the present instance, I provide an abrupt stop for the outward travel of the pinion on the screw shaft which stop comthread and in the path of movement of the shoulder 46 formed by cutting away one end of the pinion as shown in Fig. 16.

Describing the cycle of operation and be ginning with the parts in their normal position as shown in Fig.1, when the starting motorA is energized and its shaft 1 is rotated, the screw shaft will be rotated through the medium of the clutches and asso- 'i the flywheel,

' When this movement has fact that th clutches has normal manner.

ciated parts and the pinion will be caused to automatically advance into mesh with the teeth 4 of the flywheel. When this advance or inward movement of the pinion is stopped by the stop nut 6 and interposed collar 7, the pinion will partake of the rotary move ment of the screw shaft and the engine will be cranked. When the engine operates under its own power, the pinion will be automatically demeshed in the well known manner.

The torque of the motor is transmitted from the motor shaft 1 to the pinion and to the flywheel through the route and the parts as follows: The sleeve 11 being secured to shaft 1 is rotated by the motor and, in like manner, the two movable clutch members 19 and 35 being rotatively secured to this sleeve are rotated. The coiled spring being under compression and forcing the movable clutch members into engagement with their cooperating clutch members, the torque will be transmitted from these movable members to such cooperating members and through the barrel and through the clutch member 28 to the screw shaft. Inasmuch as the clutch members 18 and. 28 are both connected with the barrel and are operatively connected with the movable clutch members 19 and which, are in. turn rotatively connected with the sleeve 11, it follows that such assembly rotates as a unit.

in, case of an overload, as for instance, a flywheel that amount of resistance or in case of a backfire or a back rock with the pinion in mesh with the jaws of the clutch members are so made as toautomatically disengage by the inward movement towards each other of the movable clutch members 19 and 35 against the pressure of the been such as to cause a clearance between the clutch jaws, the sleeve and the two movable clutch members will rotate idly, and practically no torque will be transmitted in view of the e driving connection at the been broken-or disabled. When the overload decreases to the predetermined amount, the clutches will become re-engaged and the torque will be transmitted in the is stuck or oii'ers an'unusual b heavy spring 17.

pair of clutches being It will his understood that the heavy spring 17 acts as a yielding driving connectionin the normal cranking operation in view of the movable clutch members to move inwardly towards each other, tirely disengaged clutch members.

In the event that the pinion teeth and the flywheel teeth should not properly register but should abutend to end, the screw shaft is'ada ted. to move longitudinally towards the is t in Fig. 1 against the tension of the spring 38, whereupon the pinion will be moved slightly rotarily in the well known manner and registry between the teeth thereby obtained and full mesh accomplished. According to the modification shown in Fig. 22, a ring 47 is interposed between the two clutch members 19 and 35. This ring is of such width as to permit longitudinal movement of these clutch members but not separation or disconnection from their companion clutch members 18 and 28. As a result there is provided a yielding initial drive but without becoming enfrom their cooperating or transmission of torque and a positive final drive. In this form as in the preferred form, both ends of the spring 17 are utilized;

I claim:

1; An engine starter drive including a 1'0- tatable shaft, a driving member adapted to engage and drive a member of the engine to be started, a pair of clutches disposed in axial alignment, 2. spring interposed between them, a barrel enclosing the clutches and the spring, one member of each clutch being rotatively connected with the shaft and movable longitudinally with respect thereto, the other member of each clutch being rotatively connected with the barrel, and one of the latter members being operatively 7 connected with the driving member, I

2. An engine starter drive including a rotatable shaft, a driving member adapted to engage and drive a member of the engine to e started, a sleeve rotatively secured to the shaft, a pair of clutches in the form of rings encircling the sleeve, one member of each pair of clutches being rotatively secured to the sleeve and 'movable longitudinally thereon,

a barrel enclosing the clutches and rotatively.

yielding means for tending to hold the two movable clutch members into engagement with their cooperating members.

3. An en ine starter drive including s. rotatable shah, a driving member adapted to engage and drive a member of the engine to be started, a sleeve rotatively secured to the shaft, a pair of clutches in the form of rings encircling the sleeve, one member of each rotatively secured to the sleeve and movable longitudinally thereon, a barrel enclosing the clutches and r0- tatively connected with the other members of the clutches, one of the latter being operatively connected with the driving member, and a coiled spring interposed between the two movable clutch members and tending to hold them into engagement with their cooperating members.

4. An engine starter drive including a ro-' tatable shaft, a driving member adapted to engage and drive a member of the engine to be started, a sleeve rotatively secured to the shaft, a pair of clutches in the form of rings encircling the sleeve, one member of each pairof clutches being rotatively secured to the sleeve and movable longitudinally thereon, a barrel enclosing-the clutches and rotatively connected with the other members of the clutches, one of the latter being operatively connected with the driving member, and a yieldin means for tending to hold the two mova le clutch members into engagement with their cooperating members,

said barrel having means for retaining the last-named clutch members in place.

5. An engine starter drive including a to tatable shaft, a hollow shaft mounted thereon, a driving member mounted on the hollow shaft for rotary 'movement therewith and longitudinal movement thereof into engagement with amember of the engine to be started, a pair of clutches operatively connecting between the two shafts, one member of each clutch being rotatively connected with the rotatable shaft and movable longitudinally thereon, a yielding means between said latter clutch members tending to resist their longitudinal movements, a barrel enclosing the clutches and rotatively connected with the other members of the clutches, one of such latter clutch members being rotatively connected with the hollow shaft.

6. An engine starter drive including a rotatable shaft, a hollow shaft mounted thereon, a driving member mounted onthe hollow shaft for rotary movement therewith and longitudinal movement thereof into engagement with a member of the engine to be started, a pair of clutches operatively connecting between the two shafts, one member of each clutch being rotativel connected with the rotatable shaft and movable longitudinally thereon, a yielding means between said latter clutch members tending to resist their longitudinal movements, a barrel enclosing the clutches and rotatively connected with the other members of the clutches, said hollow shaft having a longitudinal yielding movement on the rotatable shaft, and being rotatively connected with one of the last men- 7 tioned clutch members.

' 7. 'An'engine starter drive including a ro tatable shaft, a hollow shaft mounted thereon, a driving member mounted] on the hollow shaft for rotary movement therewith and longitudinal movement thereof into engagement with a member of the engine to be started, a pair of clutches operatively connecting between the two shafts, one member of each clutch being rotatively connected with the rotatable shaft and movable longitudinally thereon, a yielding means between said latter clutch members tending to resist their longitudinal movements, 21 barrel enclosing the clutches and rotatively connected with the other members of the clutches, said hollow shaft having a longitudinal yielding movement on the rotatable shaft, and being rotatively connected with one of the last mentioned clutch members, and means for limiting the longitudinal movements of the hollow shaft.

8. An engine starter drive including a driving shaft, a sleeve rotatively connected therewith, a hollow shaftmounted on the driving shaft, a driving member mounted on the hollow shaft and adapted to engage a member of the engine to be started, a pair of clutches concentric of the sleeve and operatively connected with the sleeve and ollow shaft, and a. coiled spring encircling t e sleeve and interposed between the clutches with its opposite ends bearing thereagainst to hold the clutch members in clutching engagement.

9. An engine starter drive including a driv ing shaft, a sleeve rotatively connected therewith, a hollow shaft mounted on the driving shaft, a driving member mounted on the hollow shaft and adapted to engage a member of the engine to be started, a pair of clutches concentric of the sleeve and operatively connected with the sleeve and hollow shaft, a coiled spring encircling the sleeve and interposed between the clutches with its opposite ends bearing thereagainst to hold the clutch members in clutching engagement, and a barrel encasing the clutches and operatively connected with one member of each of the clutches.

.10. An engine starter drive including a driving shaft, a sleeve rotatively connected therewith, a. hollow shaft mounted on the driving shaft, a driving member mounted on the hollow shaft and adapted to'engage a member of the engine to be started, a pair of clutches concentric of the sleeve and operatively connected with the sleeve and hollow shaft, one member of each clutch being rotatively connected with the sleeve and relative ly movable longitudinally thereof, and a coiled spring interposed between said two movable clutch members to hold them normally into engagement with their cooperating clutch members.

11. An engine starter drive including a driving shaft, a sleeve rotatively connected therewith, a hollow shaft mounted on the driving shaft, a driving member mounted on the hollow shaft and adapted to engage a member of the engine to be started, a pair of clutches concentric of the sleeve and operatively connecting between the sleeve and hollow shaft, yieldmg means arranged between the clutches to normally hold the clutch members in clutching engagement, said hollow shaft being mounted for relative longitudinal movement on the driving shaft, and a spring interposed between the sleeve and hollow shaft and resisting such longitudinal movement of the latter.

12. An engine starter drive including a" driving shaft, a sleeve rotatively connected therewithya hollow shaft mounted on the driving shaft, :1 driving member mounted on the hollow shaft and adapted to engage'a member of the engine to be started, a pair of clutches concentric of the sleeve and op eratively connecting between the sleeve and hollow shaft, yielding means arranged between the clutches to normally hold the clutch' members in clutching engagement, said hollow shaft being mounted for relative longitudinal movement on the driving shaft, a spring interposed between the sleeve and hollow shaft and resisting such longitudinal movement of the latter in one direction, and

means for limiting the movement thereof in the other direction.

13. An engine starter drive including a driving shaft, a sleeve rotatively connected therewith, a hollow shaft mounted on the driving shaft, a driving member mounted on the hollow shaft and adapted to engage a member of the engine to be started, a pair of clutches concentric of the sleeve and operatively connecting between the sleeve and hollow shaft, yielding means arranged between the clutches to normally hold the clutch members in clutching engagement, said hollow shaft being mounted for relative longi tudinal movement on the driving shaft, said sleeve'having a counterbore at one end, and a spring interposed between the sleeve and hollow shaft and received by such counterbore.

1.4. An engine starter drive including a driving shaft, a sleeve rotatively connected therewith, a hollow shaft mounted on the driving shaft, a driving member mounted on the hollow shaft and adapted to engage a member of the engine to be started, a pair of clutches concentric of-the sleeve and opera tively connecting between the sleeve and hollow shaft, yielding means arranged between the clutches to normally hold the clutch members in clutching engagement, said hollow shaft being mounted for relative longitudinal movement on the driving shaft, a spring interposed between the sleeve and hollow shaft" and resisting such longitudinal movement of the latter in one direction, and means for limitin the movement thereof in the other direction comprising a pin in the clutch connected with the sleeve, and a projection companion clutch members and single yielding means for holding such movable clutch members extended and into engagement with their companion clutch members.

16. An engine starter drive including athreaded pinion, adapted for longitudinal advancement to engage and rotation to crank a member of an engine to be started, a thread-.

ed actuatingmember coacting with said pinion for advancin and rotating it, a driven a shaft, and operative connections between said shaft and said actuating member for transmitting limitedtorque from said shaft to said actuating member and permitting longitudinal yield of said actuating member, said connections including in the line of torquetransmission a clutch having members separable under applied torque and a spring opposing separation of said members and including a separate spring normally positioning said actuating member longitudinally with respect to said shaft and yieldable to accommodate interference with the advancement of said driving member by abutment against said engine member.

MAURICE P. WHITNEY. 

